Coil winding machine



Sept, 17, 1935. R. H. BURNS COIL WINDING MACHINE 3 Sheets-Sheet 1 Filed March 28, 1934 INVENTOR 7 ROBERT H. BURNS Sept. 17, 1935.

R. H. BURNS coIL WINDING MACHINE Filed March 28, 1934 s Sheets-Sheet 2 i 1/ F H 3: E /4 I6 56 \X bx E 56 if g 27 H I I 48 L in mflmu fl i WM" mi /("M llll h INN: IN

15 r4 75 1| H I I 464725 47 N I M W" W" I W N I INVENTOR I ROBERT H. BURNS BY fl ATTORNEY Sept, W, 193 R. H. BURNS y I COIL WINDING MACHINE Filed March 28, 1954 5 Sheets-Sheet 3 ullllllhn lu INVENTOR ROBERT H. BURNS ATTORNEY Patented Sept. 17, 1935 UNlTED STATES PATENT OFFICE COIL WINDING MACHINE of Delaware Application March 28,

13 Claims.

My invention relates to improvements in coil winding machines and more particularly to machines for winding heater coils of the double helical type for electron discharge devices.

The usual double helical coil winding machine is provided with a rotating and axially movable mandrel having a slot in one end to receive the mid-point of a wire of predetermined length from which the coil is to be made. After the wire has been received within the slot the mandrel is rotated in one direction and moved axially thru a die to wind the wire into a double helical coil on the man-drel. After the coil is formed the mandrel is rotated in the opposite direction and moved axially back to its original position, the coil being stripped from the mandrel during this backward movement.

These heaterv coils are usually made of very fine wire, which is diflicult for the operator to thread into the slot in the end of the mandrel. The operator frequently threads the wire unevenly, causing a coil to be formed in which one leg is longer than the other, the finished coil being defective since the legs should be of the same length. In addition to the above difficulties the die which cooperates with the mandrel during the coil winding operation is difficult to maintain in adjustment and does not always register properly with the mandrel, resulting in uneven tension on the two ends of the wire as it is being wound and causes what is known as twin or close winding, resulting in shorts between the turns in the coil.

One object of my invention is to provide an improved form of coil winding machine for manufacturing double helical coils quickly and accurately. Another object of my invention is to provide a coil winding machine in which the wire to be wound into a coil is automatically loaded into the machine and threaded into the mandrel. A further object of my invention is to provide a coil winding machine having an improved type of V described.

In the preferred embodiment of my invention the winding mandrel is rotatably mounted in a fixed sleeve and also moves axially in the sleeve. A threading mechanism is provided including a chute which moves axially with respect to the winding mandrel and which automatically threads into a slot in the end of the mandrel the mid point of a wire to be wound into a coil, the wire being loaded into the chute by means of a fluid pressure operated gun. A die mounted 1934, Serial No. 717,736 (01. 153-67) to float to a certain extent is supported to move with the chute and to receive the end of the sleeve and the mandrel prior to the winding operation when the chute is moved to threading position, the mandrel, sleeve and die always registering 5 because the floating die automatically centers itself with respect to the sleeve and mandrel. The mandrel is then rotated and moved axially thru the die to wind the wire into a double helical coil, which is removed when the mandrel is retracted thru the die.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims, but the invention itself will best be understood by referl5 ence to the following description taken in connection with the accompanying drawings in which:

Figure 1 has a plan view of a coil winding machine embodying my invention,

Figure 2 is a vertical section taken along the line 22 of Figure 1,

Figure 3 is a vertical section taken along the line 3-3 of Figure 1,

Figure 4 is an enlarged vertical section taken along line 4-4 of Figure 1 and showing details of the mandrel, loading chute and die,

Figure 5 is an enlarged front elevation of the threading mechanism made in accordance with my invention, 3

Figures 6, '7 and 8 are enlarged sectional views of the winding mandrel, threading mechanism and die at different steps in the formation of a coil made in accordance with my invention,

Figure 9 is an enlarged vertical section of the air-loading gun made in accordance with my invention, and

Figure 10 is an enlarged perspective view of the mandrel, sleeve and die partially broken away, of the winding machine shown in Figure 1, with a wire being wound into a coil.

The coil winding machine is provided with a winding mandrel which is rotated and advanced axially thru a die to wind into a coil a wire which is gripped at the middle by the end of the mandrel. The mandrel is rotatively and slidably supported in a frame and when rotated is caused to move forward by means of a lead screw fastened to the mandrel and cooperating with a fixed threaded sleeve in the frame. Rotation of the mandrel is accomplished by means of a train of gears which can be power or manually driven.

As best shown in Figures 1 to 4 inclusive, the mandrel supporting frame I0 is provided with brackets H, in which the winding mandrel I2 is supported. The winding mandrel l2 has a slot l3 in its right hand end as shown in Figures 4 and 10, in which the wire to be wound into a coil is threaded and an enlarged portion M to which is secured the lead screw [5 engaging the threaded sleeve l8 fixed in left hand bracket II. The lead screw 15 is rotated by driving mechanism comprising a driving pinion I] rotatably mounted in the right hand bracket H and splined to the lead screw 15 to rotate the lead screw and mandrel and permit also the mandrel to move axially of the lead screw l5. Thus, as the driving pinion is rotated the mandrel I4 and lead screw I5 are rotated, the lead screw advancing into or retreating out of the sleeve IE to axially move the mandrel.

Means are provided in the right hand bracket for rotatably and slidably supporting the winding portion of the mandrel I2. This supporting means includes a bushing 20 secured to the bracket l i to hold a split collar 2| (see Figures 2 and 6) for gripping a replaceable sleeve 22 which guides the winding end of the mandrel into a die, the split collar 2| being held in the bushing 20 and clamped to the sleeve 22 by the set screw 23. The sleeve 22 is provided preferably with four slots 2-4 as best shown in Figure 6, two of which are in alignment with the slot in the end of the mandrel at the beginning of the winding operation to guide the wire being formed into a coil into the forming die during the winding operation. The sleeve can be rotated to use the other two when the first two slots become worn.

The perforated die which cooperates with the sleeve and mandrel during the formation of the coil is provided with a central opening or bore into which the end of the sleeve and mandrel are inserted prior to the winding operation by moving the die toward the end of the mandrel. The mandrel is then rotated and advanced longitudinally or axially thru the die to wind the coil. To insure an accurately wound coil the die is mounted to float so that the sleeve 22 and the mandrel l4 register accurately with the die at all times. As best shown in Figures 1, 4 and G the die 25 which is preferably made of some very hard wearing material, such as tungsten carbide, and is provided with an opening or bore 26, is mounted to float in the slide 21. After the wire 28, which is to be wound into a coil, is threaded in the slot 53 in the end of the mandrel I4 in a manner to be described, the slide is moved to the left as viewed in Figure 4, the mandrel l4 and the end of the sleeve entering the opening in the die, as best shown in Figures 7 and 10, preliminary to the winding operation. As best shown in Figures 8 and 10, the mandrel is then rotated and advanced axially thru the die to form the coil, the slots 24 in the sleeve guiding the wire to be wound into the die 25 and acting with the die to feed the wire to the rotating and axially advancing mandrel at the proper points to provide proper and accurate spacing between the turns of the coil. Because the die floats, it will automatically register itself with the end of the sleeve to provide even tension in both ends of the wire during winding, the opening in the die being flared outwardly slightly as indicated in Figure 10 to guide the sleeve into the end of the die and to properly position the die with respect to the sleeve. When the coil has been wound on the mandrel, as shown in Figure 8, the mandrel is retracted, stripping the finished coil from the mandrel after which the coil can be removed thru the die by the operator.

Mechanism is provided for operating the slide to advance the die toward the end of the mandrel and to rotate and advance the mandrel thru the die. This mechanism comprises a cam and link mechanism connected to the slide to move the slide axially with respect to the mandrel and a manually operated train of gears connected to actuate the cam and link mechanism and the driving pinion l 1 connected to drive the mandrel.

The preferred mechanism for moving the slide is best shown in Figures 1 to 4 inclusive. The slide 21 carries a pin 29 connected to the cranklike link mechanism 36, 3| and 32, which is actuated by a face cam 33 mounted on the cam shaft 34, the cam shaft being rotated by means of gears 5 and 36 directly connected thru shaft 3'! to the hand-crank 38 on the front of the winding machine. As the crank 38 is rotated in a counter-clockwise direction the cam is rotated in a clockwise direction causing the link mechanism 39, 3! and 32 to which it is operatively connected to pull the slide to the left as viewed in Figure 4, advancing the die to the dotted position shown in Figure 4, to receive the end of the sleeve 22 and the slotted end of the mandrel i 2 in the bore 26 of the die as best shown in Figure '7.

After the slide has been moved to the position indicated the crank mechanism engages a train of gears for rotating the driving pinion I! to rotate and advance the winding mandrel. pinion i! is connected thru a train of gears 39, having a lost motion connection with the crank. As best shown in Figures 2 and 3, this lost motion connection is provided by means of a slot 49 and pin 4| sliding in the slot to and crank 42 on which pin 4! is connected, the crank 49 being directly connected to the hand operated crank 31 thru the shaft 31.

With the apparatus in the initial position as indicated in Figures 1 to 4, as the crank is rotated counter-clockwise the die is advanced toward the mandrel as described above, the pin 4! and crank 42 advancing from the initial position to the dotted line position shown in Figure 2, at which point the train of gears 39 begin to be positively driven to rotate and advance the mandrel axially thru the die.

Detachable stops 43 on the gear 35 and stops 44 on the frame limit the rotation of the gears and the movement of the mandrel in an axial direction. The gear 35 is provided with a plurality of holes 4-5 spaced around the gear to permit the detachable stops 43 to be shifted to permit coils of different lengths to be wound.

In accordance with my invention I provide a threading mechanism which holds and automatically inserts the wire 28 to be wound into a coil, into the slot IS on the winding mandrel l2. This mechanism comprises a chute mounted on the slide with the die to move with the die axially toward and from the end of the mandrel, and is so designed that as the chute is moved toward the mandrel, the mid point of the wire which is supported by and lies in the bottom of the chute, is inserted into the slot.

As best shown in Figures 1, 4 and 5 the chute comprises a bottom member 48 and side members 41, and a top or cover 48 pivotally mounted on the right end by pin 49 and adjustable vertically by means of screw 50 resting on one of the side members l! and attached to the top 48 by means of a bracket 5|. Adjustment of the screw 5? varies the spacing between the bottom and top members of the chute to take care of diiferent size wires inserted into the chute. At the left hand end, as

The

viewed in Figure 5, an adjustable wire stop 52 is provided for properly positioning the wire 28 in the chute so that the mid point of the wire registers with the slot l3 in the end of the mandrel l2. As best shown in Figures 6 to 8, one of the side members 5? is provided with an aperture 53 thru which the sleeve 22 and mandrel 12 can extend, the bottom and top of the chute having depressions 54, which in effect provide a round opening thru the chute. The bottom of the chute registers with the slot I3 in the mandrel so that as the chute is moved toward the mandrel, the wire which lies in the bottom of the chute will be slid into the slot prior to the mandrel entering the die 25, as shown in Figure 7. This automatic loading feature makes it unnecessary for the operator to manually thread the wire, thus reducing the strain on the operators and increasing the production in some cases by 300%.

In order to quickly load the chute and to maintain an even pressure on the end of the wire to be wound to hold it against the wire stop 52, so that the mandrel will always engage the wire 28, at its exact center point, I provide an automatic loading device making use of fluid pressure. This device is in the form of a small air gun which quickly shoots the wire into the chute and maintains the wire in its position against the stop member on the chute.

As best shown in Figures 1, 5 and 9, this load ing gun comprises an inner nozzle 55 having an interior cone-shaped funnel for guiding the wire into the opening 55 of the nozzle, and an outer nozzle 5l, which provides with nozzle 55a chamber 58 open to the atmosphere around the opening 55 in nozzle 55. Air under pressure is conducted to this chamber 58 by means of the conduit 59. Air issuing from the chamber 58 induces a suction at the tip of the gun and when a wire is inserted into the inner nozzle 55 this suction pulls the wire from the nozzle and directs it into the chute, the pressure on the end of the wire, due to the stream of compressed air issuing from the air gun, holding the wire against the wire stop 52. This nozzle is mounted to move with the chute, a fork 60 secured to the chute engaging the conduit 59.

A glass top table 55 is provided adjacent to the air gun upon which the bundle of wires to be wound into coils is supported. A light may be provided under the table to make the wires more distinguishable.

Briefly reviewing the operation of the coil winding machine, with the apparatus in the position shown in Figure l, a wire is'introduced into the air nozzle, which quickly lays the wire in the bottom 46 of the chute, the stop 5| positioning the wire so that the mid point of the wire registers with the end of the mandrel l2. The manually operated crank 38 is then rotated in a counterclockwise direction, this movement first causing the rotation of the cam 33. by means of the gears 35 and 35 to operate the crank-like link 3!], 3| and S2, and move the slide 2'! to the left, this movement resulting in the insertion of the wire into the slot is of the mandrel, as shown in Figure 7, and the entrance of the sleeve and mandrel into the bore 26 of the die. At this point the train of gears 39 is positively engaged by means of pin M and crank 35 to rotate the driving pinion I! and thus the mandrel I2, the lead screw l5 causing the mandrel to move axially thru the die to wind the wire into a coil as shown in Figure 8, the slots in the sleeve and the die causing the wire to be fed to the mandrel at the proper points and with even tension on the ends of the wire. The stops 43 and 45 in the gear 35 and the frame In limit the movement of the mandrel so that, as shown in Figure 10, when the coil 52 is completed it will have the even legs 53. To strip the coil from the mandrel, the manually operated crank is rotated in a clockwise direction which causes the mandrel to retreat thru the die, the legs 63 acting to strip the coil from the mandrel, the coil then being removed form the die by the operator.

It will thus be seen that I have provided an improved type of coil winding machine which makes a coil of the double helical type quickly and accurately by insuring proper registration of the mandrel and die and by providing an automatic loading and threading device. Coils of different length can be made by providing different length chutes and by properly setting the stops 43 on the gear 35. The pitch and length of the coils can be changed by providing lead screws of different pitch and mandrels of different diameter and length.

While I have indicated the preferred embodiments of my invention of which I am now aware and have also indicated only one specific application for which my invention may be employed, it will be apparent that my invention is by no means limited to the exact forms illustrated or the use indicated, but that many variations may be made in the particular structure used and the purpose for which it is employed without departing from the scope of my invention as set forth in the appended claims.

What I claim as new is:-

l. A coil winding machine including a winding mandrel having a slot in one end for receiving a wire to be wound into a coil, threading mechanism for placing and holding the wire in position to be engaged by said mandrel and having relative lengthwise movement with respect to said mandrel to thread the wire in said slot and driving means for first actuating said threading mechanism lengthwise of said mandrel to thread the wire in said slot and then causing relative rotation and movement of the mandrel and threading means longitudinally of the mandrel to wind said wire into a coil.

2. A coil winding machine including a winding mandrel having means at one end for engaging a wire and having a rotating and axial movement, a threading mechanism including a device for supporting a wire to be wound into a coil, said device having relative lengthwise movement with respect to said mandrel to engage the wire with the wire engaging means on said winding mandrel, and actuating means for causing relative lengthwise movement of the mandrel and said device for engaging the wire with the wire engaging means of said mandrel and for thereafter rotating and axially moving said mandrel to wind said wire into a coil.

3. A coil winding machine including a rotatable and longitudinally movable winding mandrel having a slot in one end for receiving a wire to be wound into a coil, a threading mechanism including a device for supporting the wire in registry with the slot in the mandrel and movable relatively to and lengthwise of said mandrel to place the wire in said slot, and driving means for first causing relative movement of said mandrel and said device to place an intermediate portion of the wire in said slot and then rotating and simultaneously moving said mandrel longitudinally to wind the wire into a coil.

4. A coil winding machine including a mandrel having a slot in one end for receiving a wire to be wound intoa coil, a threading mechanism for holding and inserting the wire into the slot in said mandrel, a perforated die for cooperating with said mandrel, and means for actuating said threading mechanism and for thereafter causing relative rotation and axial movement of said mandrel and die for winding the wire into a coil.

5. A coil winding machine including a rotatable and longitudinally movable winding mandrel having a slot in one end, a threading mechanism including a chute having relative axial movement with respect to said mandrel for supporting and inserting into said slot a Wire to be wound into a coil, a die having a bore registering with said mandrel, and actuating means for causing relative movement of the mandrel and chute to place the wire in said slot and for thereafter rotating and moving said mandrel longitudinally thru the bore in said die to wind the wire into a coil.

6. A winding machine having a winding mandrel adapted to engage a wire at an intermediate point, a wire guide for feeding the wire to said mandrel, said wire guide and said mandrel being mounted to be relatively rotatable and relatively movable longitudinally of said mandrel, threading mechanism for placing a wire in position to be engaged by said mandrel and fed by said wire guide, and driving means for first actuating said threading mechanism to engage the wire with said mandrel and then producing simultaneous relative rotation and longitudinal movement of said mandrel and said wire guide to wind the wire into a coil.

7. A coil Winding machine including a rotating and longitudinally movable winding mandrel having a slot in one end for receiving a wire to be wound into a coil, a threading mechanism including a chute for supporting the wire and having relative axial movement with respect to said mandrel for inserting the wire into said slot, a perforated floating die having a bore for receiving the mandrel with a wire wound thereon and actuating means for moving the chute to insert the wire in said slot and for thereafter rotating and longitudinally moving said mandrel thru the bore in the die towind the wire into a coil.

8. A coil Winding machine including a rotatable and axially movable winding mandrel having a slot in one end for receiving a wire, a threading mechanism including a chute for holding a wire to be wound into a coil transversely of said mandrel and in registry with said slot and having relative axial movement with respect to said mandrel for inserting the wire into said slot, means for laying the wire in said chute, and actuating means for moving the chute to insert the wire in the slot in the mandrel and for thereafter rotating and axially moving said mandrel to wind the wire into a coil.

9. A coil winding machine including a winding mandrel having a slot in one end, a threading mechanism including a chute having relative axial movement with respect to said mandrel for supporting and inserting into said slot a Wire to be wound into a coil, means for laying a wire of predetermined length in said chute with the mid point of said wire in registry with the end of the ing a wire to be wound into a coil transversely of the mandrel and in registry with the slot and relatively movable longitudinally of said mandrel for inserting the wire into said slot, fluid operated means for laying the wire in said chute and ac tuating means for moving said chute to insert the wire in the slot in said mandrel and for thereafter rotating and longitudinally moving said mandrel to wind said wire into a coil.

11. A coil winding machine including a rotatable and longitudinally movable winding mandrel having a slot in one end for receiving a wire, a threading mechanism including a chute for holding a wire to be wound into a coil transversely of the mandrel and in registry with the slot and having relative movement with respect to said 'mandrel for inserting the wire into said slot, a

wire stop at one end of said chute, an air gun at the other end of said chute for laying a wire of predetermined length in said chute and for maintaining said wire in position against said wire stop so that the mid point of said wire registers with the slot in said mandrel and actuating means for moving said chute to insert the wire into slot and for thereafter rotating and longitudinally moving said mandrel for winding the wire into a 40 coil.

12. A coil winding machine including a rotatable and longitudinally movable winding mandrel adapted to engage a wire to be wound into a coil,

a sleeve in which said mandrel rotates and has longitudinal movement, a perforated floating die having a bore registering with the end of the mandrel for receiving the mandrel with a wire wound thereon, and actuating means for causing relative movement of said sleeve and said die longitudinally of said sleeve tocause said sleeve and mandrel to enter the bore in said die, said actuating means thereafter causing said mandrel to rotate and advance longitudinally thru the bore in said die to wind the wire into a coil.

13. A coil winding machine including a Winding mandrel having a slot in one end to receive a wire, a threading mechanism including a chute extending transversely of said mandrel for holding a wire in registry with said slot and having relative axial movement with respect to said mandrel for inserting the wire into said slot and actuating means for moving the chute to insert the wire in the slot in the mandrel.

ROBERT H. BURNS. 

